While numerous studies have detailed the long-term effects of alcohol on the cardiovascular system, the data regarding its immediate impact had not been explored to a similar degree.
But a new study by researchers from the Harvard T.H. Chan School of Public Health suggests that even moderate consumption of alcohol may raise the risk of heart attack or stroke within an hour after drinking. The study, published in a recent issue of the American Heart Association’s journal Circulation, looked at data from 23 studies involving 30,000 participants to determine the risk rate of heart attack or stroke in the short-term and long-term periods after alcohol consumption.
Their research determined that moderate alcohol consumption—defined as one drink a day for women and up to two drinks a day for men—will cause an increase in heart and blood pressure rates that can, as study author Elizabeth Mostofsky noted, “raise a person’s risk of a heart attack or stroke approximately two-fold within the hour following consumption compared to other times.”
However, the risk drops after 24 hours unless heavy drinking continues—defined as 8 drinks a week for women and 15 or more drinks a week for men. “In other words, heavy drinking increases risk both in the short-term and the long-term, but drinking smaller amounts has different effects in the subsequent hours than it does in the subsequent days and weeks,” said Mostofsky.
The Harvard researchers acknowledge that their findings conflict with other studies that suggest regular consumption of small amounts of alcohol can lower cardiovascular risks by increasing levels of high-density lipoprotein cholesterol (HDL) and reduce the formation of blood clots, which raise the risk of heart attack and stroke.
“It is possible that the briefly higher cardiovascular risk in the hours after drinking small amounts of alcohol may be outweighed by the longer term health benefits of regular moderate drinking,” shared Mostofsky. Their findings corroborate the fact that heavy alcohol use has been associated with increased risk of heart attack and stroke “at all times studied.”
“Six to nine drinks in a day nearly doubled the risk, and 19 to 30 drinks weekly elevated the risk by up to six times more,” said Mostofsky.
